Condenser



Nov. 13, 1928.

1,691,375 E. A. BOHLMAN CONDENSER Filed Jan. 29, 1923 rnatented Nov. l3,192.8.

Unire@ STATES IPA-TENT' orrice.

ERNEST A. BOHLMAN, F CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SWITCHBOARDAND SUPPLY COM'PANY, OF CHICAGO, ILLNOIS,

A' CORPORATION OF ILLINOIS.

CONDENSER.

My invention relates to condensers, and has to do more particularly withvariable con denser-s with :in air dielectric, such as are now ingeneral use in wireless sets, and an objectJ of my invention is theprovision of an improved condenser of the variable type, ,which isprovided with structural vfeatures, which will facilitate assembly offricondenserio this type end, at the same time, provide an iimf provedcondenser structure which will permit the elieient operation of thevszi'me; i'

The condenser of my vinvention'is of the decremeter' type,' i n' whi chthe rotary plate clement and its supportingshaft', as :1 whsle, iseccentrically located inlrelntion tothe circular fixed plates, so thn'tt he=cnp:icity ofthe' Condenser maybe made/to vary as thel square of thezin-leef opertin of the` ot: tnble ele@ mont.. which1 of co 11rse,is,wcll knor'vnto'those' skilled infhefiirt, f' f One ofthe.features ofrny. invention'islhe provision ofI :1 -simplel but, eiierit-4.'idj'u's'tzible means for limitn 'r thek longitjldinzlfxnov ment ofthe .sha t carrying/ i' he" movable plates of thefine` yadju'stmetIportion' of my condenserso thetsgx'id movirhle plates' cannot4 engageor touch' theirl E xssciatfed stixt-io'nzl'ry 'plz-ttes v:indtherebyhring' about the .dischzirge of thecondenser. i' i l-Xnotlier fe'tlu'rejof, niywifriiention fthe p rovisi on :ofll Iiins O'preventihglthe of1 the s tqtionaryfiilzits edgesof the movable platesof Amy cijlriser deformed. dueI t'fthe Ldi flferent 'parts' oftm'ycondenser engaging Sid movableitndstd tioneryplntes,- when thecondenser" isoper ated to adjust sziidfinovable plntes relative to saidt-ionnrv plat-'cs thereby preventing'any possibility of :the pleit'es'engaging or'tn'c'hing,r each other to cause eshortcircu'it .of thecondenser. 1

Still another'lfeet'ui'ie my invention is'the provision ofmeans 'fortinsuring n positively closed circuit: botveenithe rotatnblelshaftscarri/ing the movnble-pl`atesof my condenser'.

For a more 'complete understanding o finy invention7 reference maybe hadto the nccornfpanyingdrawing. in `which "like reference characters inthe several views denote like parts, :ind in which;-

Fifz. l is n front elevation of the of my invention;

Fig. Q isl a plan View. of Figl;

condenser Fg. 3 is :i sectional vieivnlong the line 3--3 Fig.v l isiifsec'tioniil view'alongv the line .5F-l of Fig?,4 'i i l i Referringnow more vin detail to my inventionfas illustrated in the accompanyingdraw.- in'gs, thelconden's'er'comprises zr fixed plate element- 'A end frotatable plate :element B Ods and 7 then halve prevent the metalwashers 8 from engaging-- the edges of the other plates osaid element Bto prevent short-circuiting thoconde'ns'er."

than the diameter of the metal spacer washers 8, so that vwhen therotatableelementl is rotated .to`1 the letto causethe plates of saidrotatable element B to disengage the spaces between plates 2 of theelement A,

the irst'plate on eaeh'side'ofthe rotatablev element B will engage theperipheral-edge of the washers 8', respectively, and thereby The spacerwashers 8 are .of insulating material and not 'only preventshorfz-circuiti'ng theeondenser but also ,prevent injury to the metalplates that contact vith these`waslie'rs.

The insulation spacer washer 8 on.' the 'Eo'd 13 is da'ptedvtoengage aplate oftheelerrient D'. and. 'serves' iffr the Smepurpese as; that.

- undierstandiilfli. .l.Y

type. of rotatableplat'eph'llhp described' above in 'connectionwitl''ins'ulation was'hepsegmid the.. plates .01.the':fettarm@pele-Iment' B; S6 .tht .detailed flslcfptiilefib Same .is ndt-deemed..nefbesiiy -ffilill'llr said .plates 2 will .Sepe ided' .with airs .25.-ntegra ,vger-med .rt-riepexvi th,- n'hich are provided. lwith. suitableopei .ingsofa siz'eto'recei, i' ".'od27 'i definately' .thfmfgelesafdiemgreater diameter-nathan .thefd'anietelfof the metal washers 28,Willengage certain 'plates'2 of, the element A, and prevent, the metalwash.- ers 28 from .engaging plates 2, sothat when the..rotatableelernentB rotated with force to effect A.position of .thesames. shownin Figure l, the washers 28 striking., against certain,plates 24 of. element, tlie: e'dgzes of ot be injured and.tlielrzot'at;

able plates 2O will not engage plates'2 to eaiise Y:therplates'niesi'n's of :i ineta'li's'pacer washer 2S a short-eireuiting of thecondenser. 'the in- Sulation.wasl1ers.28 by. pre.'entin; y contact ua'lengagement of the :plates of element ,ik with washers 28 of element B,will prevent short-eireuiting of the condenser.

The otatableelemnt, D of the tine adjustment portion'V ofthe-condensercomprises a pair of plates 2O anda shaft 30, upon which 20 are mounted,the plates 2U also beingV suitably spaced from each other bj.'

i :intl clamped upon the shaft 30 by means of a nut 3l', which Y hasscrew-threaded engagement with the threaded vend'portion 30 of the shat't 30.f -Tlie free' ends of the plates kept in proper' spaced relationWith each other by ln'eansfofn a suitable. spacer washer 28', of'nonco'ri'du'cting material, and-a screw 32is provided :which 'passesthrough the spaeei'. \vasli er.2i8"and suitable openings in the 33 areprovided-which lave serewlthife'aded;engagement with the screw5 A3210',clz'xrnp .tlieplates on said serewz32.

The Ascrew .32'.,and nuts 3.3 and. .washers irifgixlditionto'lildinglthe plates 20 in fixedspaced. relatiin `with' 'each other,hold the plates 2Qlii1'aligniiierit Withea'ch other on the. shaft'.@UQQTheQivash-er 28, y engages the .middle .plete Qi; th; liuctC-m.Sierre-S for tlilesfinleipiiifposefas iv''sheis28 of the rotat# ableelement B, so that a detaileddescription of ,theisame,deemedunnecessary,' .-l'lh .o'igsmpoa @mi s's'e'mbly; @jf

'the' liied scribed`,'.1j .ivill "I iu'idle'sci ibeilthe assembl vof andD, as a whole, to

tioiiligflThfinternaediatefbase 1l is provided With'a suitable orificeof a size to permit thel insertioneoithe;shaftfO, so als-to'bring 'theadiuetment ..i5 .rt. YLIf tl-s0ndC-ese1- Whelr'the rotatabl'eplateeleine'nt D is 4in 'this position, a'base: plate B Tkprovided withsuitableforififiees' ofma lsi'zcwtoperniit it being slipped: overvtheftlir'eaded end portions of receive nuts F38@ f'hichg clamp, thefixed plate element C in positonbetireen the base 11 and plate 37..Avterniinalrneniber 38 is` provided and secured .ori-therod.14l3etu'eenthe plate.

37.1 and nut 38,1{01 purposes Well known in the Theshaft 30entends-through a suitable ope'ningin the basell, the said openingserving as aninterinediate bearing for said shaft 30,: Tliefshat`22- bfthe rotatable plate element B is Aprovided with a suitable centralopening extending its entire length aznd is of a sizeto,permititsbeing;slipped' over the shaft 30- of the rotatable plateelement D ot the fine adjuscinentportielfi Y 'ofthe'. con denser, tobringtlie' plates `2O of said elementv 20 are also r= llt] ' orificethrough which B into position with the fixed plates 2 of the clement A,as shown in Fig.l 1. 'z To retain the plates of the element B inoperative relation with the plates of the clement A', a top plate 41 isprovided, which plate has a suitable orifice to permit the shaft 22 YtoeI- tend therethrough` and screws 43 are pro'- vided which pass throughsuitable orifices also provided in the plate LMia-nd have screwthreadedengagement with the studs 9. To provide clearance for the shaftsA 22 and30 of the rotatable elements .B andv D a circular area is cut 'from thefixed platcs ati the point 144 and eccentrica-ily'displaced withrelationto the center ofthe fi.\:ed plate 2.

The shaft of the rotatable element-D. of the fine adjustment portion Voffthe 'coul denser extending through 'thesuitable central opening jinthe shaft22, it is clear that' thesaid opening'will-serve as a bearingAf or:

thesaid shaft 30. A" combined thrust"- and l frietionali leaf; spring45T is' provided fcrthe -rotatableplate' element B,- which 'isVprovidedf with a 'suitable-.- thefshaft 30 extends'.- The spring-taisarcuateimshape, and is`-se euredtoi the' base' 11? by meansi of thescrew. ''a'nd mit 48; its one end being 'lzzreivided with ani angular'extending tongue,-(mot .-:hdivnloni theA drawing) ;'wh'ich= rest in'vaisuitahleiritic'e inv the-'basalt to-preventrdtatinofthe said? spring45.1 The a tension.' 'off ther spring 45 fia such as to-ibea-n againstthe bottom-tacchi the shaft! 22 to place iitsf facer-ifm: frictinaL-ierigagcment with the 'bottom face, of'rthe :shaft 22; so-'=`t'liatasrthe rotatable lementl B iis, roi-r. tated for:tuningrpurposesgfi:willremain. in anyf` position itrzis set; dueetdfthis-lzietioxilengagement.-1 f'l-he spring' 45u-also act'saasrai thrustmeans-v as the/tensionof'thei'springat is'such ias toffoce thezshaftl22zfa'nd itsarzarte; as awhole, upward, having reference to! F lire 51; and if anydowwardrpressurefs .xerted upon the 'shaft -22,-' '=the :tension of .1the' springiissuch as. to .prevent thefshaft: from. being: forceddoivmvard an amountx .snfcielt tolcausetherotatable platesQOtOienggecthe fixed-'plates 2 to disch arge the condenserzwheh,

material, having anopening. in its oneendf through Whichthe' washer:282seculed to the shaft-30;:exter1d3. is provided,rand is:securedr'torthe lower face ofthe plate 1-1 by; the :sere w' 47 and nut4S. =-T he orifice through 'l which the 'washen-QSZ.- extends-is such-as -to eausefcontactual rfengagement, between Athe piece -Land saidwasher 28.2, sothata circuit' will always be closed :betweenLthefrotatable element Di and-the' rotatable element- B, through themedium of the washer 282,'str-i I 51, screw-47, spring 45 tothe shaft22- of element B,^.andsho'uldit happen that the shaft 22'failsto makecontact with the shaft 30, due to the Wearing away of the part-s of saidshafts, or forany other-reason, this will not the rotatable element B,and

affect the operative relation of the eli-ments B and D, as they areoperatively assoeialed with'cach other over the above traced circuit. Acombined thrust and frictional spring isnalso provided for the shaft 30of the rotatable element D vof the line adjustment portion Vi of thecondenser, and serres as a frictional spring and a thrust Spring, as discribed in connection with the springl 45' oi' a further de scription isthought unnecessary. The spring i4-also serves as a terminal for theri'ita'ialrie elements Brand D'to jconnect them uith the externalcircuit with vwliichthe condenser is connected. 'lhe rotatable clement Dci' the fine adjustment portion V is rotatable independentl'y oftherotatable element B, and a knob is providedfar'id secured to theshaft 30by suitable'means`v and when grasped b v theope'ratofr,- may lie-turned,the Said shaft 30 f turningl Yin-.the l'bearing in f 'thef shaft 22formed Eby the opening in .said sha-ft 22. "From the above description',it may be seen th'atwhen the dial- 50 is' turned, the'rota'tableelement' B :"is'lrotated' independently of 4 the shaffti'SO of the'rotatable element D, and when ther proper' tuning is.` accomplishedthrough the'ined-ilin'o'the'retatable element B in ass'ociation; with;the: .fixed elementA A, the -said element B is held iii positionbymeans' of the sprin'ga.- If aigfurther-andfiner tuning isdcsiredtoelariy the. incoming signals, the knob 6035s grasped and thevrotatable mtatedfzunti'li :the: Ydesired result isobtained.- Thespringlis of suchtension; as to hold the rotatable element D at norma! whilethe rotatable-element B is rotated, and alsoas lo overcomefany. rictionthat may be set up betureenithe .shaft 30gandthejcentral: opening in theshaft.22,'wherr itl'isj'turned. j l .l-.The sha-ft 30- isf: subject tolong rit-udinalmovement against the tension of spring- 54,:Indi-shouldpressureA be exterted' againstrtho kinobrtiOpseeured to the'shaft- 30, suliciently to overcome the tension of said spring,saidshaft.\vi1l1n0\ e longitudinally in a. downward direction,`andu'nless'means is-provided orlizniting-th'e movement ofsaid shaft inthisdirection, the rotatable plates 20 of element-D secured to'theshaft30 will be brought into engagement with tlx'e-i \;ed plates 2 o element.C, whereby adischarge of the condenser will be effected. Now, in orderto limit. the. downward-1 longitudinal movement. oi' the shaft 30 toprevent the touching-of the platea 2 and plates 20 of the elements C andD, respectively, I provide-a cyiindrical n'ieznber 'having atappedoriice extending centrally therethrough, and which member T0 issnitably secured in a. suitable opt-.ning in the plate 37 so-that thesaid tapped orifice in member 70 is directly below and in alignment withthe the shaft 30-- A screw 711 and 'a nut 'f2 are also provided, saidscrew having Scrmv-t-hreaded -engagementgwtih the nut 72'and tappedorilice in the member 70. The screw 7l extends through the member 70such a distance as not to normally engage the end of the shatBO, but vetfar enough so that it will engage the said shaftl before the platessecured to the shaft 30 will engage or touch the fixedplates of elementC, when theshaftismoved in a. downward direction. Vhen the proper spacebetween the end of the screw 71 and end of shaft 30 is obtained, the nut72 is'screwed up tightagainst the end of the member to hold said screw71 in its adjusted position relative to'shaft 30. Vhen ai differentadjustment is desired, the nut 72may befloosened and the screw 7loperated to eifeetanother adjustment. 'Thus it will beseenfrom theabove-tbat'l'have provided adjustable means for limit-ingthe'longitudinal movement' of the shaft' 30 to prevent diseharg'eofithecondenser. B v limiting the longitudinal move-f ment of the "shxp'f't-30;' it'wv1l 'alsobeseen -thatl the sha-pe-andten'sion of tl1e'spx2i1i.g=54is:pre vented from being aiected "by: thefi'novemnt of said shaft;30,-forl the mbveinentothef shaft 30f' \vere not,4 limited. itf'lnightpossibly happen thatthe'spring "54Awouldfbe iiiisshapedl or deformed bykanv `=extremej entlwise movement of said shaft gfwhicliavouildvresultin effecting the 'engagement-lofi the iplatesind 2O 'of theelem'etsffandD. i Mara-da AStuds' 67! andisrewsx''taiedovdediimdsuitably'l secured inl the'top plat'efllf .for iper. mitt-ing'lthe condenser; 'as alunit; t'olie-mounted and' secured to 'a suitablemount'i'ng member;*Whe'ihavedese'ribed and llustratedth condenser 'my invention A"inpreferred form, iti is to be understood tl'iat=chang'es andmodificationswill rezi'fli'ly u'ge's'tl themselves to th ose skill ed?in= the rtf aiidI lesirei'to cover all s ucli cha-n iesandmdiiiolitisfsfcome w'vthin thefspirt-- 'and lscope 6ft-lieza'ppe'cedlgimggjf @zt-'fami ed? feriiizLf; niema- .fama 'Havngdescried"rr'ivfinventiifwhat@ cl'aiin- 'as' nevvfrid 'desir .itoisollrebybetit/er l'l 'f "1i .ii Nii'l'i'rln zi a 'pliimlity of j`movable memb'ersfp'sitioned parallel, to said stzitgi'o'narymiembersgfind opl eratively associate dfiv ith fsh'id'stationarjhnembers, 'a'l 'sha-itl for 'Said {inofvafblejnieinbers and adapted :to movein' rotarjfand'flotiiitiidinafl direction, springfmeansjjor opposi frlongili tudinal movement of-1saidslafti a-iid-lfoi'j'f-'ie-- storing;A'and retaining sai'rllshaftf inI fior-'mal en divise' f position, andLista-ble' olimiting the longitudimilfinoveiiieo'f-Isaid shait'toprevent engagemntoff'saidmovable members 'withfsaid stationary"insulationjnean's secured?betweenl so'n'e'o-tlfie said plaies.mfpregveaigth bmitactiiairpgagf ment' 0f :eend 'movable'andfsadiemiliana@ plates when-saidsliaft'is'inoved -nt'irotI "dii recth. *1.21..f 'A1-i 2. 'AL' :device (VE-'fthe'A character' 'des'eribe'dgli'nimer-abe rs; and

roeierscluding,r a stationary element7 a movable ele# ment operativelyassociated with said sint-ionaiy element, a shaftyi'or said movableelement, a second stationaryT element, and a movableeler-.ientassociatedtherewith, a shai't for said second morable element, said second .shaftbeing in contaetualengagement with the said first shaft whereby acircuit is closed through said shafts 'for said movable elements andmeans for effecting' a circuit for said morable'elementsthrough saidshafts even though said shaftsfail-to' make contactual engage-4 mentwith each other, Said last means also serving to maintain-tbe movableelements in any position to whichfthey are operated.

A device of the character described, including a paiiofstationarycondense;` plates, movable: condenser I plat-es or cooperation with saidstationary 'condenser iplates, ,shafts su )ertin0V said; movablecondenser )lates .fe-.aid shafts adapted te be in :contactualengagem'ent with eachother-:to elos'e'a circuit through: 'saidlmovable-'condenser plates, ani in-V dependent ,elecrial- `conductorconnect-ing tli'ersetsofA movable ;con`denserplates,l said conductorserving-smeans for, maintaining said-movable plates-in-any adjustedposition. d .4.''In|?z devices'oi the character described,v including a.stationary 'elementand?. a 111051,-, able elementi; said @elementsinfoperative'e rcla'fv in: Wihl each other: andfeach comprising tapluralityv of plates, insulation m'eans Jforl said stationary'elementadapte'rLto. engage the peripheralfedgetoicertain of the platesfsaidiov'ableiele'menti tol-prelvent contact-ual engagenitfosaidstationany'and movable elemening-andi insulation-i means-forsaidmovzible'zelexent-fadapted; to engage ther-periphe eralfzed'ge. oferta'imowthe plates of said, stir. tionarlyqeleieb toit-preventleontactual en"-l gagementlrof Sidfmo'vable element and',` -sta-itioriiiry elemento-z uinzfi .'..--ii1-' .f1 -/.5.'-'Infai.device ofthe'oara. ter described, including i fstationaryrelementsf and-z `movableelexn'entsaif'eael .eompnsing a :plurality hoiplatesandtinaoperatixte:associatidnwwithaehl other;- insulation 'fuiensz'fori esaidf; Stationary; elementsi'adaptedfttoiienfiag the.peripheral: edge' off'certan'rof; Vtih 'platesof' Athe movable: lementsfor l'preventing i eontaetul .engage-4 mento saidinovablef:elemnts withsaid sta-z tionar'yf elementswirenisai'dfniovable elements are iin a"teertin'iiipositlion-,ff and insulation nieansifor-1s`zii'd mb'vablelem'entsladapted to enga'gofthe peripheral edge' of certain of the plaftes ofit-hefsttionary'zelements -for:preventiii'gfcontaotualf-'engiagement of `said `movable ele'mentsfwithsaidf'stationary elements when sifid n'iovable elements are infanothercertain IQ'SitSOiff "ff, fr; fif,

-f/G lln dev ice ofthe eliara'oter described in; hidingV a? plurality'iof stationary 44plates-a phzrality of l'movable-:platesffsaid4statioi'ary plates 'a-nclfs'aid2 Imovablelplatesbeingl in` op?erative'assoiationvithi ''ach vother andv indie itin Cil

.ing operatively insulation washers for said stationary-:platesincluding la #plurality Y'oit stationaryI plates separated by 'metalwashers, :a lpli'irality of :notable plates separated by inetal washers,said slatioiiaryplatesand movable rplate's'beassociated witlii e'achother,

'for' preventing 'coi'ita'ctal-engagement of said movable plates withsaid lirstliietal washers, and insulation washers for said movableplates for preventing contactual engagement of said movable plates withsaid second metal washers.

8. A device of the character described, including a stationary element,a movable element for cooperation therewith supported on a shaft movablein a longitudinal and a rotary direction, individual insulating meanssecured in each of said elements for preventing cont-actual engagementof said movable element with said stationary element when in certainpositions, and spring means for preventing such said engagement whensaid shaft is moved in a longitudinal direction.

9. An electrical device of the character described, including astationary element having a plurality of plates, a rotatable elementhaving a plurality of plates and operatively associated with saidstationary element, insulation members for said stationary element of alesser hardness than the hardness of the plates of said rotatableelement and adapted to be engaged by plates of said rotatable elementwhen the same is rotated in one direction to prevent deformity of theplates of said rotatable element, and insulation means of a lesserhardness than the hardness of the plates of said stationary element andadapted to be engaged by plates nient when the same is rotated inanother direction to prevent deformity of the plates o said rotatableelement, said'insulation members also serving to prevent electricalconnection between the plates of the stationary element and the platesof the rotatable ele ment.

10. In a device of the character described, a stationary element havinga plurality of plates, a movable element having a plurality of plates,said elementsoratively associated with cach other, non-conductingyielding means for said stationary element for en` gaging the peripheraledge of certain of the plates of said movable element to preventengagement of said first element with said second element, and toprevent deformation of w VMJA condenser to--the other; vplementing'.oneol' the-condenser 4sides and or' said rotatable elethe plates of;said;movable element, and non- Vconducting yielding means for Saidmovable eleine'nt for certain of the plates osaid stationary elementengaging the peripheral edge of to prevent engagement of said tirst andsec- '.ond-gele'ments, and to prevent deformation of the plates 'of saidstationary element.

including 2 condenser sides; onebfavhiclris adjustable with respect -acondenser plate element supiIiountedto-iturn with? respect; to bothrcondenser, sides; fand; ii'ieansincluding a` spring jmernber for'completing an electrical? circuit by'engagiiig the" supplemental plateelement vandth'e 'coiideiiser si'defsupplied with this 12. A condenserincluding 2 condenser sides; one of which is adjustable with respect tothe other; a condenser plate element supplementing one of the condensersides and mounted to turn with respect to both condenser sides; aninsulating base member located between the supplemental plate elementand the said 2 condenser sides, and means including a spring member anda terminal member operative on each side of said base member forengaging the suplemental plate element and the condenser side suppliedwith this plate element to complete an electrical circuit between thesupplemental plate element and the condenser side with which it isassociated.

13. A condenser including 2 condenser sides; one of which is adjustablewith respect to the other; a condenser plate element supplementing oneof the condenser sides and mounted to turn with respect to bothcondenser sides; means engaging the supplemental plate element and thecondenser side supplied with this plate element including a Yterminalplate against which the supplemental plate element is thrust by otherspring means, all of said means, including said spring means, adapted tocomplete an electrical circuit.

14. A condenser including 2 condenser sides; one of which is adjustablewith respect to the other; a condenser plate element sup plementing oneof the condenser sides and mounted to turn with respect to bothcondenser sides; an insulating base member located between saidsuplemental plate element and said 2 condenser sides, means, operativeon opposite sides of said base member for engaging the supplementalplate element and the condenser side supplied with this plate elementincluding a terminal plate against which the supplemental plate elementis thrustby other spring means, said sprin means adapted to maintain theadjustable element and the supplemental plate element in any position.

15. A variable condenser ofthe character described including astationary element hav` ing. a-plural-ity:iof=stationaiy-zplates,spacing members between-saidplates;v a rotor.' element-for--said1condenserincludingra plurality of 4ing electrical engagementbetween said rotor :plates nnd said stationaryelement.

i 1G. A-variabl'e condenser.=of theicharcter described rinelndingalstationary -element compris-ingr ap1i1rality ot r plates, 4spacingmembers between said'plates, a Irotor element for f said condenserincluding fa plurality-of platesadapted to rotatebetween'said-Stationarv plates. nrreecentrically located sliaft'for said rotorelement, one or morefo'flsai'd'spactween said stationaryz plates, aneccentrically y located Shaft for rota-ting said rotor plates between.said stationary plates, one of said spacing members .being ofinsulating f mate- A.

rial-:to prevent'elcetrical-Contact between said -r0tanyplatesand otherofsaid spacingmem- :Signed byiiiiejatCl-licago, iii-tbel county of Cook,:n-d, State flllinois, this 26th day of J aliuarys1923.

ERNEST- A. B OlfILMAN.V

